Hi Dina,
so - yes it is true that in the generic EN15804 method, some categories are empty, namely those that are not LCIA method categories but rather inventory based categories. Reason is that when applying the method, users would anyhow need to modify data sets so that, e.g., use of renewable energy is implemented as elementary flow, in each data set where relevant, by creating and adding then a "use of renewable energy elementary flow" to the processes. This flow should then be added to the respective impact category as well.
The EN15804 EuGeos database, also available on Nexus, contains already a database adapted to meet EN15804 requirements, and together with the database we are providing an LCIA method that contains the respective "pseudo elementary flows" (such as use of renewable energy elementary flow from above) in the categories.
Hope this helps!
Andreas